飞机语音告警系统智能检查仪的设计

设计了某现代战机语音告警系统的智能检查仪，详细介绍了该检查仪的硬件及软件。该检查仪具有功能多、测量精度及自动化程度高、可靠性及兼容性好、操作简便等优点。     

LD抽运高功率连续波1.34 μmNd∶GdVO4激光器研究

报道了利用光纤耦合大功率半导体激光器 (LD)抽运Nd∶GdVO4晶体 ,采用平凹谐振腔 ,输出 1 34μm波长的高功率连续波固体激光器。在抽运功率为 1 4 75W时 ,获得最大输出功率为 4 6 2W ,光 光转换效率为 31 3% ,斜率效率达 32 9%。利用实验测得的阈值抽运功率和斜率效率 ,计算了Nd∶GdVO4晶体在 1 34μm波长处的受激发射截面     

多级染料激光放大器中激光增益与放大自发辐射强度的理论研究

利用激光增益和放大自发辐射 (ASE)理论 ,对不同条件下的染料激光放大器的激光增益和ASE强度进行了数值计算。分析了当入射光强远小于和大于有效饱和光强时 ,激光增益和ASE强度与入射光相对强度的关系 ,讨论了在两种条件下ASE系数以及染料池端面反射系数对激光增益和ASE成分的影响。最后利用这些结果 ,对连续激光的多级染料放大系统的优化设计进行了讨论。     

高速贴片机优化软件的设计与开发

SMT生产线要达到最大的产量,必须要考虑生产线的效率。贴片机是SMT生产线中的关键设备,因此提高贴片机的生产效率具有十分重要的意义。本文以松下贴片机为例,介绍了贴片机程序优化软件的设计与开发中的思想、方法和经验,希望对从事CAM软件研究的工程人员有一定帮助。     

A novel method to evaluate clustering algorithms for hierarchical optical networks

The routing issues in multi-layer and multi-domain optical networks have drawn much attention in current research. With the introduction of the path computation element, routes can be calculated more efficiently in multi-domain optical networks. However, the optimal degree of routing approach in multi-layer and multi-domain optical networks is also determined by the clustering algorithms deployed for construction of hierarchical networks. Therefore, it is important to investigate the way to evaluate the impact of the clustering algorithm on the routing approach (e.g., blocking probability) in optical networks with dynamic traffic, which has not been studied sufficiently. In this paper, a novel method to describe and evaluate the clustered structures generated by different clustering algorithms for hierarchical optical networks is proposed. This method deploys a novel evaluation metric that represents blocking probability of clustered optical networks, so it can be used as guidelines for designing clustered structures. Besides theoretical analysis, simulations are carried out on different network topologies and clustered types to validate the effectiveness of the method presented.     

External Stimuli Responsive Liquid‐Infused Surfaces Switching between Slippery and Nonslippery States: Fabrications and Applications

Surfaces with controllable liquid wettability and related functions have gained increasing attention from interfacial scientists due to the high demand of fundamental research and practical applications. Inspired by pitch plant's excellent liquid repellency, external stimuli responsive lubricant‐infused surfaces switching between slippery state and nonslippery state under external stimuli (E‐LIS) have been developed by introducing external stimuli responsive materials as substrates, lubricants, or repellent liquids. This progress report is focused on recent development of E‐LIS. First, design strategy and fabrication of E‐LIS upon external stimuli exposure, including stress, electrical field, magnetic field, and temperature, is summarized. Then, emerging interfacial applications of E‐LIS, such as microreactors, pipetting devices, fog collection devices, and so on, are highlighted. In addition, remaining challenges and future prospects are provided.     

Anhydride‐Assisted Spontaneous Room Temperature Sintering of Printed Bioresorbable Electronics

Bioresorbable electronic devices are promising replacements for conventional build‐to‐last electronics in implantable biomedical systems and consumer electronics. However, bioresorbable devices are typically achieved by complex complementary metal oxide semiconductor fabrication processes that minimize exposure to humidity. Emerging printable techniques for bioresorbable electronics demand further improvement in electrical conductivity and mechanical robustness. This paper presents a room‐temperature spontaneous sintering method of bioresorbable inks that contain zinc nanoparticles and anhydride. The entire process can be conducted in atmosphere environment under 90% humidity within 300 min. It has minimum requirement for external heating and special ambient conditions, allowing humidity to trigger the surface chemistry of zinc nanoparticles and spontaneous welding between neighboring nanoparticles. The resulting bioresorbable patterns are highly conductive (σ = 72 400 S m^?1) and mechanically robust (>1500 bending cycles) to enable practical applications. A radio circuit achieved through the above method can operate stably over 14 days in air and disappear in water for less than 30 min. The spontaneous room‐temperature sintering represents a rapid and energy‐efficient approach to achieve high‐performance bioresorbable electronics with improved mechanical robustness and electrical performance, leading to broader impacts in the areas of healthcare, information security, and consumer electronics.     

浅谈自然博物馆展示中几个有效的结合

那些国际知名的自然博物馆通常都有着几百年的历史,随着社会的发展,公众对自然博物馆的期望不仅仅只是按阵列摆放的珍奇柜,他们更希望能与这些标本有亲密的接触和深入的了解。这些老牌的自然博物馆已经行动起来了,他们或者局部地改变,或者全新地再建,在这个过程中他们较好地处理了传统与现代、共性与个性、大空间与小互动、收藏与开放之间的关系。     

直流变换器软开关技术综述

近几十年来,随着功率密度的提高,DC/DC变换器软开关技术取得了很多成就。从谐振变换器、软开关-PWM变换器以及移相全桥软开关变换器三个方面对直流软开关技术进行了综述,比较了各种软开关技术的优缺点;对进一步提高软开关变换器效率的改进方法进行了展望。     

无速度传感器矢量控制下的火电机组高压辅机 变频器低电压穿越技术仿真研究

为了提高火电机组高压辅机变频器的调速性能和低电压穿越能力,本文对基于瞬时无功功率MRAS的无速度传感器矢量控制进行了设计和仿真研究,并分析了该控制方法下的变频器低电压穿越技术.仿真表明,该控制方法不仅可以有效提高高压辅机调速性能,还可以缩短变频器因低电压停机后的重启时间,减少辅机的转速下降,更加快速有效地实现低电压穿越.